Bunsen and similar burner



p 1939. H. M. ULLMANN 2,171,816

BUNSEN AND SIMILAR BURNER Filed July 50, 1937 Jnventor HHRR) M. ULLMHNN attorney Patented Sept. 5, 1939 UNITED STATES PATENT oFFieE 6 Claims.

This invention relates to improvements in Bunsen and similar burners and more particularly to means forming a part of or associated with such burners for substantially reducing, if not entirely eliminating, the fire hazard heretofore present in the use of such burners.

It is generally known that probably the most frequent cause of serious fires and conflagrations in laboratory and other buildings in which Bunsen burners with rubber connecting tubes are employed is due to the very common phenomenon known as backfiring or striking back of the burners. After a burner has struck back and ignited at the base the lower part of the burner, includ- 15 ing the present metallic inlet tube becomes very hot, and in fact so hot that the rubber connecting tube frequently melts off, or breaks 01f, or otherwise becomes damaged and wholly or partly disconnected from the metal inlet tube of the burner. When this occurs the stream of gas flowing through the damaged end of the rubber tube ignites and this frequently is the cause of a serious confiagration. It is, therefore, an object of the present invention to eliminate the fire hazard 25 due to the striking back of a Bunsen or similar burner.

The above object is accomplished in accordance with the present invention by providing the burner with means for preventing the rubber tube from being melted or otherwise broken off or disconnected from the inlet tube of the burner due to the excessive heating of the tube by the heat generated when the burner strikes back. More specifically, said object is accomplished in accord- 35 ance with the preferred embodiment of the present invention by providing the burner with a metallic inlet tube of such length that the heat generated when the burner strikes back will be dissipated suificiently, if not entirely, so that the 40 end of said metallic tube to which the rubber tube is connected is always maintained at a safe temperature below that at which the rubber tube is harmfully affected, whereby heat impairment of the connection of said rubber tube with said 45 inlet tube is prevented.

I have found that when the metallic inlet tube is lengthened suificiently for accomplishing the above object of the invention, the additional weight tilts or tends to tilt the burner whereby 50 the latter may be upset. Another object of the invention, therefore, is to eliminate this disadvantage, and this is accomplished in accordance with the preferred embodiment of the invention by bending the inlet tube at a point spaced from 55 the base of the burner to provide an additional support which not only obviates the disadvantage referred to but in addition provides a more stable support than was heretofore provided.

It is also another object of the invention to provide means for connecting the rubber tube to 5 the burner in such manner that said rubber tube will lie flat on the table, thus additionally substantially reducing if not entirely eliminating the danger of the burner being upset. v

The above objects of the invention and other objects ancillary thereto will be fully understood from the following description considered with reference to the accompanying drawing which illustrates the embodiment of the invention.

In the drawing, the figure shows a Bunsen burner provided with means embodying the present invention.

Referring now more particularly to the drawing, the invention is illustrated in connection with a Bunsen burner I of conventional construction provided with the usual combustion tube H and the usual short metal gas-inlet tube l2 positioned above the supporting base M. It will be understood that as heretofore used the rubber tube for conducting the gas to the burner is connected to '25 the end of said short inlet tube I2. In accordance with one form of the present invention, however, the metal inlet tube 12 is lengthened for the above described purpose by connecting inlet tube section l6 at one end l8 thereof to the end of said short tube or tube section. The usual rubber tube 20 is connectedto the other end 22 of tube section l6.

Tube I6 is composed of metal of good heat conductivity such, for example, as copper or brass and is of sufiicient length to dissipate the heat generated when the burner strikes back, so that said tube never becomes hot enough in the region of its connection with rubber tube 20 to melt off or otherwise deleteriously affect said rubber tube at its connection with the metal inlet tube. While the length of said metal inlet l6 may vary within practical limits, I have found that when it is about six or seven inches in length the region thereof adjacent its end 22 always remains sufficiently cool to obviate damage to the connection therewith of the rubber tube. As here shown, inlet tube section IE is detachably connected to the usual short inlet tube l2 of the conventional burner, whereby the benefits and advantages of the present invention may be applied as an attachment to such burners, particularly those already manufactured or in use. It will be understood, however, that inlet tube section It may be formed as an integral part of tube section l2, or

in other Words, the Bunsen burner may be provided initially with a metal inlet tube of sufficient length for accomplishing the object of the present invention.

As previously explained, the additional weight of the lengthened metal inlet tube has a tendency to tilt and sometimes to upset the burner. While this disadvantage may be obviated in several ways, the arrangement which I have provided as lustrated herein is preferred. For this purpose tube section I6 is, as here shown, provided with a bent portion 24 so dimensioned that the lower surface thereof is substantially in the same plane with the bottom surface of base Id of the burner. Further in order that rubber tube 20 may lie fiat on the table or other support for the burner the outer end portion of tube l6 beyond bend 24 is disposed close to the bottom of bend 24, but is preferably slightly raised thereabove so that the connecting end of rubber tube 20 will clear the surface of the table.

Thus it is seen that the construction herein shown and described is well adapted to accomplish the several objects of the present invention. It will be understood, however, that certain changes in the construction and arrangement of parts may be made and will occur to those skilled in the art in view of the present disclosures. Accordingly, I do not wish to be limited precisely to the construction herein shown and described except as may be required by the appended claims considered with reference to the prior art.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A burner of the class described comprising a combustion tube, a metal gas-inlet tube connected to said combustion tube and subject to the heat generated in the burner when the latter strikes back and adapted to be connected at its outer end to a rubber gas-conducting tube, said metal gas-inlet tube having a length such that heat transferred thereto when the burner strikes back will be sufiiciently dissipated to prevent heat-impairment of the connection therewith of the gas-conducting tube.

2. A burner of the class described comprising a combustion tube, a metal gas-inlet tube connected to said combustion tube subject to the heat generated in the burner when the latter strikes back and adapted to be connected at its outer end to a rubber gas-conducting tube, said metal gas-inlet tube having a length such that heat transferred thereto when the burner strikes back will be sufficiently dissipated to prevent heat-impairment of the connection therewith of the gas-conducting tube, and a bent portion provided in said inlet tube to aid in supporting the burner.

3. A burner of the class described comprising a combustion tube, a metal gas-inlet tube connected to said combustion tube subject to the heat generated in the burner when the latter strikes back and adapted to be connected at its outer end to a rubber gas-conducting tube, said metal gas-inlet tube having a length such that heat transferred thereto when the burner strikes back will be sufiiciently dissipated to prevent heat-impairment of the connection therewith of the gas-conducting tube, and a bent portion provided in said metal inlet tube to aid in supporting the burner, the outer end portion of said metal inlet tube being positioned to provide for connecting the gas-conducting tube close to the bottom of the burner so that said conducting tube will be substantially fiat on the support for the base of the burner.

4. A burner of the class described comprising a base, a combustion tube upstanding from said base, and a metal gas-inlet tube connected to the burner above said base in communication with said combustion tube, said metal inlet tube having a downwardly bent portion adaped to engage the support on which the burner is positioned.

5. A burner of the class described comprising a base, a combustion tube upstanding from said base, a short metal gas-inlet tube connected to the burner above said base in communication with said combustion tube, and a relatively long metal gas-inlet tube detachably connected at one end to said short tube and adapted to be connected at its other end with a rubber gas-conducting tube.

6. A burner of the class described comprising a base, a combustion tube upstanding from said base, a short metal gas-inlet tube connected to the burner above said base in communication with said combustion tube, and a relatively long metal gas-inlet tube detachably connected at one end to said short tube and adapted to be connected at its other end with a rubber gas-conducting tube, and means provided in said relatively long tube to prevent tilting of the burner on its base.

HARRY M. ULLMANN. 

